The World Wide Web is the Internet's multimedia information retrieval system. In the Web environment, client machines communicate with Web servers using the Hypertext Transfer Protocol (HTTP). The web servers provide users with access to files such as text, graphics, images, sound, video, etc., using a standard page description language known as Hypertext Markup Language (HTML). HTML provides basic document formatting and allows the developer to specify connections known as hyperlinks to other servers and files. In the Internet paradigm, a network path to a server is identified by a Uniform Resource Locator (URL) having a special syntax for defining a network connection. So called web browsers, for example, Netscape Navigator (Netscape Navigator is a registered trademark of Netscape Communications Corporation) or Microsoft Internet Explorer, which are applications running on a client machine, enable users to access information by specification of a link via the URL and to navigate between different HTML pages.
FIG. 1 shows an example of typical a web browser graphical user interface (“GUI”) display on a browser computer. On a portion (100) of a user's computer display, a web browser (110), in this example Netscape Navigator, runs in its own window. In this example, the web browser is currently pointed to the top-level or home page of the example web site, as indicated by the URL http://www.corp.com in the location bar (140). This web page, “index.htm”, is configured to split the GUI display into three frames. The upper frame (120) is used to display a general banner, the left frame (130) is used to display a list of hyperlinks from the top-level web page (or navigation bar), and the right bottom frame (150) displays the contents of the currently selected web page. The top of the web browser display includes a row of control icons, including a “back” button (160) and a “forward” button (170). Additionally, a domain history button (180) provides a drop down history list of the URLs of web sites most recently visited by the browser application.
When the user of the web browser selects a link, the client issues a request to a naming service to map a hostname (in the URL) to a particular network IP (Internet Protocol) address at which the server is located. The naming service returns an IP address that can respond to the request. Using the IP address, the web browser establishes a connection to a server. If the server is available, it returns a web page. To facilitate further navigation within the site, a web page typically includes one or more hypertext references known as “anchors” or “links”.
In FIG. 2, a typical tree-like hierarchical organisation of links within a web site is shown, where a given link (200) typically points to other Web resources (210, 215), and those resources may point to still other resources (220,222,224,226,228). Thus, a given top-level link often has an associated set of lower level links, which may point to still more resources located across many different servers in the network. Navigation through multiple levels of links is often very difficult. The goal of many users of the Internet is to “drill down” to a given piece of information that represents some desired content. Because HTML pages are often statically coded, however, a user often has little choice but to load successive web pages in search of a given web page that might hold the content of interest. This approach is time consuming, and it often results in the user either terminating the navigation of a particular site or simply not finding the relevant content. Additionally, when traversing these multiple levels of links, the user often loses track of the sequence of links used to arrive at a particular web page of interest. Thus, the user could have difficulty in returning to a particular web page after further web pages have been subsequently browsed, if it were necessary to repeat the process of traversing the multiple levels to find that particular web page again.
A bookmark facility is one way of addressing this problem by providing a mechanism to store and recall specific web pages of interest. Each bookmark comprises the title of the web page and the URL used to access the web page. Additionally, bookmarks often contain the date on which the web page was last visited and the date on which the web page was book-marked, along with additional information.
Another approach to this navigation problem is provided by built-in navigation functions in currently available web browsers, which use the history log and allow users to revisit previously opened web pages. A “back” button, such as button 160, backtracks the user's browsing sequence one web page at a time to show the previous web page. After the user has returned to a previous web page, the “forward” button, such as button 170, is enabled, allowing the user to browse to the forward-most web page in the user's browsing sequence. Sometimes, a user may descend multiple layers into a web site in such a way that the “back” button must be clicked several times to return to the top-level web page.
While the bookmark and backtracking tools give the user certain limited flexibility in revisiting web pages, the tools limit the user to a single branch in the browsing path. Thus, there is a need for a user to be able to revisit web pages with fewer mouse clicks and also revisit web pages within multiple branches in the browsing path.
FIG. 3 shows another approach that enables the user to keep his or her place in a tree of information, that is, the conventional built-in web browser function of opening multiple web browser windows. Therefore, if a particular first web page (300) is opened within a first web browser window (310) and the user then opens a second web browser window (330) to view a second web page (320), the first web page (300) can be retrieved for viewing by re-selecting the first web browser window (310). However, this has the disadvantage of requiring an extra web browser window to be opened which is time-consuming, an extra overhead and also clutters the screen display. Thus, there is a need for a user to be able to keep their place in a tree of information within a single web browser window.
U.S. patent application Ser. No. 09/310914, filed May 13, 1999 discloses a method and apparatus for implementing direct link selection of cached, previously visited links in nested web pages. A pointer is added to each web page identifier, which points to the previous linking web page in the navigational path. Another pointer may be added to each web page identifier, which points to the next linking web page in the navigational path. The web browser is thereby enabled to store and display information regarding a navigational path for accessing linking network node addresses.
U.S. patent application Ser. No. 09/210198, filed Dec. 10, 1998, discloses a recursive link navigation interface method. More specifically, a link map associated with a parent link in a web page is built using a client-side or server-side process. The link map, which includes URLs, text descriptors or actual thumbnail web page images, is selectively displayed at a client web browser when a user takes a given action with respect to the parent link. Thus, for example, when the user hovers over the link with a mouse operation, the link map is displayed to enable the user to determine whether further navigation (through the parent link) is desirable. While the link map is displayed, the user may, alternatively, jump to another link (in the link map) without first traversing the parent and (perhaps other) subordinate links.
U.S. patent application Ser. No. 09/687091, filed Oct. 10, 2000, discloses a method for browser history thread sibling management. The user may use the conventional “back” and “forward” buttons to traverse backwards and forwards within a browsing history thread, respectively, as well as use the “UP” and “DOWN” keys to traverse to the next and previous sibling browsing history threads, respectively.
U.S. patent application Ser. No. 09/704596, filed Nov. 3, 2000, discloses a multidimensional browser visual history thread viewer. A user may visually review multiple visual browsing history sessions in a two-dimensional array, or panel, of visual history viewers. The user may select a multidimensional visual history review tool, which causes an array of pop-up viewers to be displayed, each replaying a different web browser visual history session, simultaneously.
Thus, there is a need to be able to store the web page that is currently being displayed, so that when a user chooses another navigation path and arrives at a different web page, it is possible to switch between the web pages contained within different navigation paths, with ease.